Cryogenic refrigerator and regenerative heat exchange material

Abstract

A cryogenic refrigerator includes a first refrigerant filled in a final refrigerating force storage chamber on a high temperature side thereof and consisting essentially of a composition expressed by (a) (Er.sub.(x) R.sub.(1-x)) 3 Ni.sub.(y) Co.sub.(1-y), or (b) Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Cu.sub.(1-y) wherein 0≦x≦1, 0≦y≦1, and R denotes a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc, a second refrigerant filled in the final refrigerating force storage chamber on a low temperature side thereof and consisting essentially of a composition expressed by (f) Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Co.sub.(1-y), or (g) (Er.sub.(x) R.sub.(1-x)) 3 AlC.sub.(y) wherein 0≦x≦1, 0≦y≦1 and R represents a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc, and a partition member for separating the second refrigerant from the first one so as to not be mixed in the refrigerating force storage chamber.

What is claimed is: 
     
       1. A cryogenic refrigerator capable of creating a higher refrigerating capacity by expanding compressed helium gas after it is cooled while being passed firstly through a first refrigerating force storage chamber at a first cooling stage and finally through a final refrigerating force storage chamber at a final cooling stage, said cryogenic refrigerator comprising: a first refrigerant filled in the final refrigerating force storage chamber on a high temperature side thereof and consisting of a composition expressed by:   (a) a formula: (Er.sub.(x) R.sub.(1-x)) 3  Ni.sub.(y) Co.sub.(1-y) wherein 0≦x≦1, 0≦y≦1 and R represent a rate earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc,   (b) a formula: Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Cu.sub.(1-y) wherein 0≦x≦1, 0≦y≦1, and R denotes a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc,   (c) a formula: Er.sub.(x) Dy.sub.(1-x) Ni 2  wherein 0≦x≦0.85, or   (d) a formula: Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Co.sub.(1-y) wherein 0≦x≦1, 0≦y≦1 and R denotes a rare earth element selected from the group consisting of Gd, Tb, Dy and Ho,   a second refrigerant filled in the final refrigerating force storage chamber on a low temperature side thereof and consisting of a composition expressed by:   (e) a formula: Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Co.sub.(1-y) wherein 0≦x≦1, 0≦y≦1 and R denotes a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc,   (f) a formula: (Er.sub.(x) R.sub.(1-x)) 3  AlC.sub.(y) wherein 0≦x≦1, 0≦y≦1 and R represents a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc,   (g) a formula: Er.sub.(x) Dy.sub.(1-x) Ni 2  wherein 0.85≦x≦1,   (h) a formula: (Er.sub.(x) R.sub.(1-x)).sub.(1-y) Ru.sub.(y) wherein 0.5≦x≦1, 0≦y≦0.7 and R represents a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc, or   (i) a formula: Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Cu.sub.(1-y) wherein 0≦x≦1, 0≦y≦1, and R denotes a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc; and   a partition member for separating the second refrigerant from the first refrigerant so as not to be mixed in the final refrigerating force storage chamber.   
     
     
       2. The cryogenic refrigerator according to claim 1, wherein said second refrigerant filled in the final refrigerating force storage chamber occupies 10-90 vol % relative to all of refrigerants filled in the final refrigerating force storage chamber. 
     
     
       3. The cryogenic refrigerator according to claim 1, wherein said first refrigerant consists essentially of a composition expressed by a formula (Er.sub.(x) R.sub.(1-x)) 3  Ni in which 0≦x≦1 and R represents a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc. 
     
     
       4. The cryogenic refrigerator according to claim 3, wherein said first refrigerant consists essentially of a composition expressed by Er 3  Ni. 
     
     
       5. The cryogenic refrigerator according to claim 1, wherein said first refrigerant consists essentially of a composition expressed by the formula (Er.sub.(x) R.sub.(1-x)) 3  Ni.sub.(y) Co.sub.(1-y) in which 0≦x≦1, 0≦y≦1 and R denotes a rare earth element selected from the group consisting of Y, Pt, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc. 
     
     
       6. The cryogenic refrigerator according to claim 5, wherein said first refrigerant consists essentially of a composition expressed by the formula (Er.sub.(x) R.sub.(1-x)) 3  Ni.sub.(y) Co.sub.(1-y) in which 0≦x≦1, y is one of 0, 0.1, 0.15, 0.2, 0.3, 0.5 and 1, and R represents a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc. 
     
     
       7. The cryogenic refrigerator according to claim 5, wherein said first refrigerant consists essentially of a composition expressed by Er 3  Ni.sub.(y) Co.sub.(1-y) in which 0≦y≦1. 
     
     
       8. The cryogenic refrigerator according to claim 7, wherein said first refrigerant consists essentially of at least one of a composition selected from the group consisting of Er 3  Co, Er 3  Ni 0 .15 Co 0 .85, Er 3  Ni 0 .2 Co 0 .8, Er 3  Ni 0 .3 Co 0 .7 and Er 3  Ni 0 .5 Co 0 .5. 
     
     
       9. The cryogenic refrigerator according to claim 1, wherein said first refrigerant consists essentially of a composition expressed by (Er.sub.(x) R.sub.(1-x))Ni.sub.(y) Cu.sub.(1-y) in which 0≦x≦1, 0≦y≦1 and R represents a rare earth element selected from the group consisting of Y, Pt, Nd, Sm, Eu, GD, Tb, Dy, Ho, Tm, Yb and Sc. 
     
     
       10. The cryogenic refrigerator according to claim 9, wherein said first refrigerant consists essentially of a composition expressed by (Er.sub.(x) R.sub.(1-x))Ni.sub.(y) Cu.sub.(1-y) in which 0≦x≦1, y is 0.5 or 0.6, and R denotes a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc. 
     
     
       11. The cryogenic refrigerator according to claim 9, wherein said first refrigerator consists essentially of a composition expressed by (Er.sub.(x) R.sub.(1-x))Ni in which x is one of 0.6, 0.75, 0.8, 0.85, 0.9, 0.95 and 1 and R denotes a rare earth element selected from the group consisting of Y, Gd, Dy, Ho and Yb. 
     
     
       12. The cryogenic refrigerator according to claim 11, wherein said first refrigerant consists essentially of at least one of a composition selected from the group consisting of ErNi, Er 0 .9 Yb 0 .1 Ni, Er 0 .7 Ho 0 .3 Ni, Er 0 .75 Gd 0 .25 Ni, Er 0 .85 Gd 0 .15 Ni, Er 0 .9 Gd 0 .1 Ni, Er 0 .95 Gd 0 .05 Ni, Er 0 .9 DY 0 .1 Ni, Er 0 .9 Y 0 .1 Ni, Er 0 .8 Y 0 .2 Ni and Er 0 .6 Y 0 .4 Ni. 
     
     
       13. The cryogenic refrigerator according to claim 9, wherein said first refrigerant consists essentially of a composition expressed by ErNi 0 .6 Cu 0 .4. 
     
     
       14. The cryogenic refrigerator according to claim 9, wherein said first refrigerant consists essentially of a composition expressed by HoNi 0 .5 Cu 0 .5. 
     
     
       15. The cryogenic refrigerator according to claim 1, wherein said first refrigerant consists essentially of a composition expressed by Er.sub.(x) Dy.sub.(1-x) Ni 2  in which 0≦x≦0.85. 
     
     
       16. The cryogenic refrigerator according to claim 15, wherein said first refrigerant consists essentially of a composition expressed by Er.sub.(x) Dy.sub.(1-x) Ni 2  which x is at least one of number selected from the group consisting of 0, 0.2, 0.6, 0.8 and 0.85. 
     
     
       17. The cryogenic refrigerator according to claim 1, wherein said second refrigerant consists essentially of a composition expressed by Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Co.sub.(1-y) in which 0≦x≦1, 0≦y≦1, and R denotes a rare earth element selected from the group consisting of Y, Pt, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc. 
     
     
       18. The cryogenic refrigerator according to claim 17, wherein said second refrigerant is a composition expressed by (Er.sub.(x) R.sub.(1-x))Ni in which x is at least one of number selected from the group consisting of 0.6, 0.75, 0.8, 0.85, 0.9, 0.95 and 1, and R denotes a rare earth element selected from Y, Gd, Dy, Ho and Yb. 
     
     
       19. The cryogenic refrigerator according to claim 18, wherein said second refrigerant consists essentially of at least one of a composition selected from the group consisting of ErNi, Er 0 .9 Yb 0 .1 Ni, Er 0 .7 Ho 0 .3 Ni, Er 0 .75 Gd 0 .25 Ni, Er 0 .85 Gd 0 .15 Ni, Er 0 .9 Gd 0 .1 Ni, Er 0 .95 Gd 0 .05 Ni, Er 0 .9 DY 0 .1 Ni, Er 0 .9 Y 0 .1 Ni, Er 0 .8 Y 0 .2 Ni and Er 0 .6 Y 0 .4 Ni. 
     
     
       20. The cryogenic refrigerator according to claim 17, wherein said second refrigerant consists essentially of a composition expressed by ErNi.sub.(y) Co.sub.(1-y) in which y is at least one of number selected from the group consisting of 0.7, 0.8, 0.9 and 1.0. 
     
     
       21. The cryogenic refrigerator according to claim 17, wherein said second refrigerant consists essentially of a composition expressed by Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Co.sub.(1-y) in which x is at least one of number selected from the group consisting of 0.6, 0.75, 0.8, 0.85, 0.9, 0.95 and 1.0, y is at least one of number selected from the group consisting of 0.7, 0.8, 0.9 and 1.0, and R represents a rare earth element selected from the group consisting of Y, Gd, Dy, Ho and Yb. 
     
     
       22. The cryogenic refrigerator according to claim 1, wherein said second refrigerant consists essentially of a composition expressed by (Er.sub.(x) R.sub.(1-x)) 3  AlC.sub.(y) in which 0≦x≦1, 0≦y≦1, and R represents a rare earth element selected from the group consisting of Y, Pt, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc. 
     
     
       23. The cryogenic refrigerator according to claim 22, wherein said second refrigerant consists essentially of one of a composition selected from the group consisting of Er 3  AlC 0 .5, Er 3  AlC 0 .75 and Er 3  AlC. 
     
     
       24. The cryogenic refrigerator according to claim 1, wherein said second refrigerant consists essentially of a composition expressed by Er.sub.(x) Dy.sub.(1-x) Ni 2  in which 0.85≦x≦1. 
     
     
       25. The cryogenic refrigerator according to claim 24, wherein said second refrigerant consists essentially of one of a composition selected from the group consisting of Er 0 .85 Dy 0 .15 Ni 2  and ErNi 2 . 
     
     
       26. The cryogenic refrigerator according to claim 1, wherein said second refrigerant consists essentially of a composition expressed by (Er.sub.(x) R.sub.(1-x)).sub.(1-y) Ru.sub.(y) in which 0.5≦x≦1, 0≦y≦0.7, and R denotes a rare earth element selected from the group consisting of Y, Pt, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc. 
     
     
       27. The cryogenic refrigerator according to claim 26, wherein said second refrigerant consists essentially of one of a composition selected from the group consisting of Er 0 .7 Ru 0 .3, Er 0 .65 Ru 0 .35 and Er 0 .60 Ru 0 .40. 
     
     
       28. A cryogenic refrigerator capable of creating a higher refrigerating capacity by expanding compressed helium gas after it is cooled while being passed firstly through a first refrigerating force storage chamber at a first cooling stage and finally through a final refrigerating force storage chamber at a final cooling stage, said cryogenic refrigerator comprising: a first refrigerant filled in the final refrigerating force storage chamber; and   plural kinds of second refrigerants filled in the final refrigerating force storage chamber, and   a partition member for separating one of the second refrigerants from the other of the second refrigerants so as to not be mixed in the final refrigerating force storage chamber,   wherein one of said second refrigerants is constituted by at least one composition selected from compositions expressed by the following formulas (a)-(g);   (a) a formula: (Er.sub.(x) R.sub.(1-x)) 3  Ni.sub.(y) Co.sub.(1-y) wherein 0≦x≦1, 0≦y≦1 and R represents a rate earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc,   (b) a formula: Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Cu.sub.(1-y) wherein 0≦x≦1, 0≦y ≦1, and R denotes a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc,   (c) a formula: Er.sub.(x) Dy.sub.(1-x) Ni 2  wherein 0≦x≦0.85,   (d) a formula: Er.sub.(x) R.sub.(1-x) Ni.sub.(y) Co.sub.(1-y) wherein 0≦x≦1, 0≦y≦1 and R denotes a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc,   (e) a formula: (Er.sub.(x) R.sub.(1-x)) 3  AlC.sub.(y) wherein 0≦x≦1, 0≦y≦1 and R represents a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc,   (f) a formula: Er.sub.(x) Dy.sub.(1-x) Ni 2  wherein 0.85≦x≦1, or   (g) a formula: (Er.sub.(x) R.sub.(1-x)).sub.(1-y) Ru.sub.(y) wherein 0.5≦x≦1, 0≦y≦0.7 and R represents a rare earth element selected from the group consisting of Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Sc,   one composition is filled on a high temperature side of the final refrigerating force storage chamber, the other compositions are filled on a low temperature side of the final refrigerating force storage chamber, and a magnetic phase transition temperature of said one composition is higher than a magnetic phase transition temperature of said other compositions.   
     
     
       29. The cryogenic refrigerator according to claim 1, wherein said first and second refrigerants are granular. 
     
     
       30. The cryogenic refrigerator according to claim 28, wherein said first and second refrigerants are granular.